1. Field of the Invention
The present invention relates to a light source system, and more particularly, to a light source system for stereoscopic projection.
2. Descriptions of the Related Art
For most of conventional light source systems for stereoscopic projection, a color wheel or two liquid crystal switches are used to transform a first light beam and a second light beam generated by a light source system into a left-eye view angle image and a right-eye view angle image respectively, and then the left-eye image and the right-eye image are projected to eyes of a viewer.
Specifically, if a color wheel (for example, an RGB color wheel) is used as a light splitting element, then the color wheel must have at least six filtering regions so that three filtering regions (i.e., a red filtering region, a green filtering region and a blue filtering region) are allocated to each of the left and the right eyes. In practical operation, the user can view a stereoscopic image by simply wearing a pair of passive glasses. However, it is difficult to reduce the volume of the color wheel because the color wheel must have at least six filtering regions and the focused point on the filtering regions must be large enough to keep passing light with a small incident angles; in other words, this arrangement makes it difficult to miniaturize the light source system for stereoscopic projection.
On the other hand, if liquid crystal switches are used for light splitting, then the problem that a mechanical mechanism is liable to wear can be solved because the liquid crystal switches require no use of the mechanical mechanism. However, the liquid crystal switches must be operated precisely at a precision higher than that of the color wheel; and furthermore, particular attention shall be paid to the problem of synchronism in the design, and otherwise, it would be impossible for the user to see a stereoscopic image or the stereoscopic image seen would have a poor quality. Briefly speaking, when the liquid crystal switches are used, the light source system for stereoscopic projection becomes relatively complex and costly.
Accordingly, an urgent need exists in the art to provide a light source system for stereoscopic projection that can be used with a pair of passive glasses and that has a low cost, a simplified optical arrangement, a miniaturized volume or improved brightness.